1. Field of Invention
This invention relates to electric machines, both motors and generators. The invention is applicable to machines running at constant speeds or at continuously variable speeds and elevation and traverse actuators for full circle and circle segments. The invention is also applicable to linear motions analogous to the above. Such motors are used, for example, in magnetic disc memories, in robotics, numerically controlled machines, turrets and in many other applications. The invention can also be applied to provide a machine having an operation analogous to a solenoid.
2. Related Art
Stepping motors using a magnetic reluctance principle have been described, for example, in the German Offenlegungschrifts Nos. 3124352, 3123540 and 3121547. These patents describe constructions and configurations of the stator and rotor which seek to attain certain construction advantages.
British Pat. No. 2157089 describes a single phase reluctance motor which uses solid mild steel stator poles and rotor poles.
It is an object of the present invention to provide a machine of this kind with a plurality of discrete magnetic circuits preferably each made up of a plurality of thin laminations or magnetically oriented domains of a composite material and to provide these in a multiple phase arrangement.
A related object to the aforegoing is to provide a design in which the laminations are assembled lying in planes which are parallel with (rather than orthogonal as in conventional electric machines) the axis of rotation of a rotational machine.
It is a further object to provide a multiple phase machine which is simple to make, in which the magnetic circuits are fitted or moulded around simple spool windings and robot manufacturing techniques may be facilitated.
Another object is to provide modular components from which different machines having widely different operating speeds or numbers of actuator positions can be assembled with differing numbers of the modular components. This allows the speed of the machines to be adapted over a wide range to the speed of the load or power source without the use of a gearbox.
Finally it is an object to provide a machine which can be made to function, at will, as either a motor or a generator and to provide regenerative braking if required.